Assessment of Depression and Anxiety

Understanding Screening Tools

• The PHQ-9 is a 9-item self-report scale assessing symptoms of major depressive disorder, focusing on depressive symptoms and accompanying functional impairment 1
• The GAD-7 is a 7-item self-report scale assessing probable causes of generalized anxiety disorder 2
• Score interpretation for PHQ-9 includes: 1-7 indicating minimal symptoms, 8-14 indicating moderate depressive symptomatology, 15-19 indicating moderate to severe depressive symptomatology, and 20-27 indicating severe depressive symptomatology 3
• Score interpretation for GAD-7 includes: ≥5 indicating mild anxiety, ≥10 indicating moderate anxiety, and ≥15 indicating severe anxiety 4

Clinical Implications and Recommendations

• For PHQ-9 scores ≥8, conduct further diagnostic assessment to identify the nature and extent of depressive symptoms and determine presence or absence of a mood disorder 1, 3
• For PHQ-9 scores 8-14, consider low-intensity interventions such as guided self-help based on cognitive behavioral therapy or structured physical activity programs 3
• For PHQ-9 scores ≥15, refer to psychology and/or psychiatry for diagnosis and treatment 3
• For GAD-7 scores ≥10, consider pharmacologic treatment such as SSRIs, which have shown efficacy in treating generalized anxiety disorder 5
• Special attention should be given to item 9 of PHQ-9 regarding self-harm thoughts; any positive response warrants immediate risk assessment 3

Common Pitfalls to Avoid

• Failing to complete the full assessment when initial screening items suggest depression or anxiety 3
• Omitting the self-harm item (item 9) from PHQ-9 assessment, which may artificially lower scores and miss critical risk information 3
• Not considering medical or substance-induced causes of significant depressive or anxiety symptoms, which should be determined and treated first 1
• Overlooking the common comorbidity between depression and anxiety - approximately 31% of patients with an anxiety disorder also have major depressive disorder 5

Integrated Assessment Approach

• When multiple diagnoses are present, prioritize treatment for the condition causing the greatest functional impairment 5
• For any patient identified as at risk of harm to self and/or others, refer to appropriate services for emergency evaluation 4

Assessment of Distress and Functional Impairment in Mood Dysfunction

Initial Screening Approach

• The American Society of Clinical Oncology recommends using validated screening tools with established cutoffs to quantify both symptom severity and functional impact, then conduct targeted diagnostic assessment when scores exceed clinical thresholds 6, 7, 8, 9, 10
• For specific populations where PHQ-9 may be less accurate, the American Society of Clinical Oncology suggests using the Geriatric Depression Scale (GDS-30 or GDS-SF-15), with cutoffs of ≥19 for full scale or ≥5 for short form, for elderly patients 7, 9
• The American Society of Clinical Oncology recommends using the Hospital Anxiety and Depression Scale (HADS), which excludes somatic symptoms that may be confounded by medical illness, for cancer or medically ill patients; scores ≥8 on either subscale indicate caseness 7, 9, 10

Diagnostic Assessment Algorithm

• The American Society of Clinical Oncology recommends conducting comprehensive diagnostic evaluation when PHQ-9 ≥8, GAD-7 ≥10, or DT ≥4 with concerning problem list items 6, 9, 11, 12
• Before diagnosing a primary mood disorder, the American Society of Clinical Oncology suggests ruling out medical and substance-induced causes, including uncontrolled pain or fatigue, delirium from infection or electrolyte imbalance, thyroid disorders, medication side effects, and substance use or withdrawal 6, 9, 10

Practical Implementation Strategy

• The American Society of Clinical Oncology recommends administering PHQ-9 and GAD-7 to all patients with suspected mood dysfunction, and adding SDS to quantify functional impairment across work, social, and family domains 6, 7
• For scores above threshold, the American Society of Clinical Oncology suggests conducting structured diagnostic interview to confirm DSM-IV criteria and assess for medical causes 6, 9
• The American Society of Clinical Oncology recommends basing treatment intensity on both symptom severity and functional impairment, not symptoms alone, and making full functional recovery—not just symptom remission—the treatment goal 6, 9

Laboratory Evaluation and Referral Guidelines for Severe Depression and Anxiety

Essential Laboratory Tests and Referral Criteria

• The American Society of Clinical Oncology recommends evaluating for medical causes including thyroid function tests, complete metabolic panel, complete blood count, vitamin B12 and folate levels, and toxicology screen to rule out medical and substance-induced causes of depressive and anxiety symptoms in patients with severe depression and anxiety 13
• The clinical team must determine when referral to a psychiatrist, psychologist, or equivalently trained professional is necessary as a shared responsibility, particularly for patients with PHQ-9 scores ≥15, indicating severe depressive symptomatology 13
• Review of current medications for potential mood-altering side effects, such as interferon, corticosteroids, and beta-blockers, is crucial in patients with severe depression and anxiety, as these medications can contribute to depressive and anxiety symptoms 13

Management of Severe Generalized Anxiety Disorder (GAD‑7 ≥ 15)

Score Interpretation

• The GAD‑7 uses severity thresholds of ≥ 5 for mild, ≥ 10 for moderate, and ≥ 15 for severe anxiety. [14][15]
• A score of 19 falls well within the severe range and is associated with substantial functional impairment across home, work, social, and relationship domains. [14][15]
• Severe anxiety is characterized by excessive, uncontrollable worry about multiple topics together with physical symptoms such as restlessness, difficulty relaxing, irritability, and fear of catastrophic events. 15

Immediate Safety Assessment

• Before any other evaluation, clinicians must assess for risk of self‑harm or harm to others, severe agitation, psychosis, or delirium. [14][15]
• Any identified safety concern mandates an emergency psychiatric evaluation, irrespective of the GAD‑7 score. 15

Medical and Substance‑Induced Evaluation

• Potential medical contributors to anxiety should be systematically investigated and treated before labeling the presentation as a primary anxiety disorder. 15
• Clinicians should review all current medications for anxiety‑inducing side effects, especially corticosteroids, beta‑agonists, stimulants, and thyroid hormone therapy. 15
• Assessment of substance use—including caffeine, stimulants, alcohol withdrawal, and benzodiazepine withdrawal—is required. 15
• Uncontrolled pain, fatigue, or infection‑related delirium that can manifest as anxiety must be evaluated. 15

Comprehensive Diagnostic Assessment

• When the GAD‑7 score is ≥ 10, a full diagnostic assessment is required to delineate the nature, extent, and specific type of anxiety disorder. [14][15]
• The assessment should document specific anxiety symptoms (e.g., panic attacks, trembling, sweating, rapid breathing, tachycardia, palpitations). 15
• It must also capture severity, duration, and functional impairment in home, occupational, social, and relational settings. 15
• Exploration of precipitating stressors and periods of heightened vulnerability is recommended. 15
• Patients with generalized anxiety often exhibit excessive worries that extend beyond medical concerns and are disproportionate to actual risk. 15

Referral and Treatment Initiation

• All individuals scoring in the severe range (GAD‑7 ≥ 15) should be referred to a psychiatrist, psychologist, or equivalently trained mental‑health professional. [14][15]
• Evidence‑based treatment should combine pharmacologic options (e.g., antidepressants, anxiolytics) with non‑pharmacologic therapies such as cognitive‑behavioral therapy, psycho‑educational support, and structured physical activity, delivered by appropriately trained providers. 15
• Initiation of treatment should occur only after any medical contributors to anxiety have been adequately addressed. 15

Common Pitfalls to Avoid

• Failing to assess for suicidal ideation or self‑harm risk in patients with severe anxiety, especially when comorbid depression is present. 15
• Overlooking medical causes (e.g., hyperthyroidism, excessive caffeine, medication side effects) that may fully explain or significantly contribute to anxiety symptoms. 15
• Delaying specialist psychiatric referral for severe anxiety (GAD‑7 ≥ 15) under the assumption that reassurance alone will resolve symptoms. [14][15]